Mia tiptoed down the hall. She paused at her brother's doorway. Leo was bouncing on one sneaker. His other foot wore a pink slipper. "We're going to be late," he said.
She spotted a crumpled library book on his desk. The corner was bent. "Where's the other one?" she asked. Leo pointed at the book. "Have you seen my book?" he said.
Mia crouched and peered under the bed. Dust bunnies scattered. She pulled out a toy truck, a sock, and — yes! — Leo's sneaker, wedged behind a pile of papers. "Found it!" she said.
Leo slipped the sneaker on. His eyes went wide. The book was still gone. "We'll find it," Mia said, tucking the sneaker under her arm. She marched toward the door.
They marched into the classroom. Mia checked the reading nook. Nothing but a stack of picture books. She checked her cubby — a lunchbox, a raincoat, a half-eaten apple. The book was not there.
Leo checked the art table. A paintbrush wiggled. "That's strange," Mia whispered. She picked up the brush. It was still wet. Blue paint gleamed on the bristles.
Mia followed the trail. Blue paint marks zigzagged across the floor. They snaked past the easels, dipped under tables, and stopped right at the bookshelf. Leo gasped.
There, tucked behind a row of encyclopedias, was his book. Its cover was splattered with blue paint. "It's my book!" he cried. Mia pulled it free. The pages were stuck together.
Mia opened the book carefully. The paint had made strange shapes — a blue mountain, a spotted animal, a winding river. Leo leaned in close. His eyes grew wide with wonder.
"It's a treasure map," Leo said. Mia grinned. She tucked the sneaker into her pocket. She held the book up like a flag. "Then let's go find the treasure," she said.
Leo grabbed her hand. They ran out of the classroom together. Their footsteps echoed down the hall. Adventure awaited.
The trail of blue paint led them somewhere new. Somewhere full of mystery. Somewhere they would explore together.